Patio heater



FIG. 1 is a perspective view looking slightly upward showing my new design;

FIG. 2 is a side view thereof;

FIG. 3 is a perspective view looking slightly downward thereof; and,

FIG. 4 is a top plan view thereof.

The bottom forms no part of the claimed design. The subject matter shown with broken lines forms no part of the claimed design. 

I claim the ornamental design for a patio heater, as shown and described. 